A LAN cable (Local Area Network cable) is a cable that is necessary when using a wired network, and that is used to mutually connect various network devices.
It is essential to use the aforementioned LAN cable in not only large scale facilities equipped with large scale network facilities, such as general companies, government offices, schools, hospitals and the like, but also where small scale network devices are installed, such as small offices, restaurants, houses and the like.
When a problem occurs in such network devices, the operator must first find out into which port of which device the LAN cable is inserted.
Large scale network devices, that are installed in large scale facilities, such as large companies, government offices and the like, are mutually connected via an enormous number of LAN cables. Therefore, with the conventional method of individually checking both ends of a plurality of LAN cables that connect the network devices, it is difficult for the operator to identify into which port of which device the LAN cable is inserted.
In order to facilitate the operation of checking the LAN cables described above, conventional technologies used the method of attaching a tag to each LAN cable. For this method to be properly effective, in the case of replacing or exchanging a network device, the tag must be replaced as well. However, this replacement operation described above is not being implemented perfectly in the field due to operators being replaced and the negligence of maintenance and so on. Therefore, due to the un-replaced tags, it takes a lot of time and manpower to repair and maintain the network.
For the operation of checking the LAN cables, a technology was proposed to install an LED in each LAN cable connector at the receiving side and at the transmitting side, and to apply external power to identify whether the LEDs at both sides are turned on.
This technology operates normally under the standards of data transmission speed of not more than 100 Mps, but under the standards such as CAT5E, CAT6, and CAT7 where data must be transmitted at a speed of 100 Mps or above, problems such as decrease of data transmission speed and data blocking occurred due to the external power source.